The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.
Reviewed By: nemanja, nikic
Differential Revision: https://reviews.llvm.org/D135474
ACC registers are a combination of four consecutive vector registers.
If the vector registers are assigned first this often forces a number
of copies to appear just before the ACC register is created. If the ACC
register is assigned first then fewer copies are generated when the vector
registers are assigned.
This patch tries to force the register allocator to assign the ACC registers first
and then the UACC registers and then the vector pair registers. It does this
by changing the priority of the register classes.
This patch also adds hints to help the register allocator assign UACC registers from
known ACC registers and vector pair registers from known UACC registers.
Reviewed By: nemanjai
Differential Revision: https://reviews.llvm.org/D105854
ACC regsiters are a combination of 4 consecutive vector regsiters and therefore
somtimes require special treatment for register allocation. This patch only
adds a test.